Photographic shutter.



J. RICHARD.

PHOTOGRAPHIC SHUTTER. APPLlcATloN man rima, 1914.

1,201,764. Patented 001;. 17,1916.

141111111' fan". 1r '1211.11 1 I Fig.

JULES RICHARD, OF PARIS, FRANCE.

PHOTOGRAPHIC SHUTTER.

Specication of Letters Patent.

Patented Oct. 17, 1916.

Application filed February 3, 1914. Serial No. 816,243.

Y of France, have invented Improvements in Photographic Shutters, ofwhich the following is a full, clear, and exact description.

When it is required to make an instantaneous exposure with photographicapparatus it is desirable, in most cases, that the shutter of suchapparatus should operate with extreme rapidity. With leaf shutters inparticular, which for many reason-s are to be preferred to blindshutters, the speed is limited as much by the strength of the spring,which cannot exceed a certain value, as by the action of the brakeprovided to regulate the duration of the exposure, which always causes acertain resistance.

The present invention relates to 'an improvement in photographicshutters permitting the speedl of the instantaneous operation of theshutter to be more than doubled, when this is desired.

The improvement comprises, in principle, the connection of themovablemember of the brake -bymeans of a spring to the lever controlling therelease of the second leaf of the shutter, and the combination with thisbrake of a device for restraining the said movable member from moving,in such a manner that no departure from an ordinary setting of the partsis made when the shutter is operated to give an instantaneous exposureat a moderate orl normal speed, while when it is required to give a veryrapid instantaneous exposure, the brake is put completely out of action,and the supplementary spring adds its 'effect to that of the ordinaryspring to effect the movement of the lever causing the release of thesecond leaf of the shutter. The accompanying drawings show how i thesaid invention can be conveniently and advantageouslycarried intopractice in its application to a leaf shutter provided with an airbrake. Y

In thisdrawing: Figure 1 is a front elevation of ashutter frame-plate..Fig is a rear elevation of the same. F1g. 3 1s a detail. view, partlyin section, drawn to a 60 larger scale, Fig'. 4 shows a section on theline A--A, Fig. 3. Figs. 5 and 6 are detail views illustrating theoperation of the shutter. Fig. 7 is a detail view ofone of the shuttermembers. Fig. 8 is a detail view of the other shutter member.

As shown in this drawing, the shutter comprises two superposed leaves aand b, arranged in the usual manner, the leaf a provided with a pin cwhich engages with the lip of a lever d pivoted at all) The leaf b isprovided with a pin e which can be retained by the lip f2 of a lever fpivoted at f1. The leaf a is under the control of a 'spring g, and theleaf b is under the control of a spring L. The lever f can be actuatedby a lever z' pivoted at z'l. This lever is under the control of aspring j, it is moreover combined with an air brake or damper c.

In accordance with this invention, the lever z' is connected to thepiston o of the brake by a spring Z, the coils of which touch each canbe moved so as to abut against the piston 0.

To provide for setting the shutter or movother and a slider m carries arod a which ing the same toretracted position, the plate y a is providedwith a pin a which passes through a slot s in plate b and projectslaterally therefrom. The pin a is engaged by the forked end of' a leverr2 pivoted at r. A lever 7' is connected to the forked lever r2 andoperates to swing the same about its pivot 7". A movement ofthe forkedlever r2 in the direction of the arrow in Fig. 2 will cause plates 'aand b to move toward the right, whereupon the pin c carried bv plate awill be positioned behind the hooked end of the lever d and the pin ecarried by plate l b will be positioned behind and engaged by the end f2of the lever f. During this movement of the plates a and b, the pin 3will engagethe upper end of the lever 'i and move the same to the right.With the slider m in the position shown in Fig. 5, the movement of thelever i will draw the piston o to the left within the cylinder s withoutplacing the spring Z under tension by reason of the construction thereofas hereinbefore described.

If the trigger p is preed the leaf a is set free and, under the actionof the spring g moves toward the left and uncovers the len-ses. Thismovement of the plate a to the left withdraws pin a from engagementwithlever z' and permits said lever to turn about its pivot i underinfluence of the spring j. This lever i as it reaches the end of itstravel acts on the edge f3 of the lever f which thereupon sets free thepin e. The second leaf b is then moved by the spring it and covers thelenses. In both these movements, the spring Z acts as a connecting rodbetween the leveri and the piston 0 since for this purpose the spring isso made that the spirals thereof rest in Contact with one another whenthe spring is not under tensile stress. However when the slider m is putinto the position 2, Fig. 6, this is no longer the case, but in settingthe shutter the piston o is prevented from moving in its cylinder by therod n. From this it results that in setting the shutter, the spring Z isextended. The lever z' is therefore acted Aupon simultaneously by theordinary spring j and by the spring Z which now operates as asupplementary spring to the spring j.

At the instant of release, the lever z' turns under the combined actionof the two springs j and Z. Moreover no resistance is opposed to itsmovement since the piston o does not move in its cylinder. Under thesecircumstances the movement of the lever i is accomplished very rapidlyand the time elapsing between the movements of the first and secondleaves of the shutter may be reduced to one live-hundredth of a second.This is a shutter speed which is more than double the speed which hasheretofore been given by leaf shutters.

The slider m may be controlled by a single trigger or preferably, asshown, it-

can be` actuated by a milled button 9 carrying a pinion engaging in arack 9'- integral with the slider, but any other suitable device can beemployed for this purpose, for example, a lever or an eccentric.

By taking care to stop the movement of the piston by an appropriatesetting of the rod n or by any other suitable abutment, it is alsopossible to put the spring Z under slight tension, even in the case inWhich the shutter is required to give normal instantaneous exposure. Itis also possible to combine a short movement of the piston with acorresponding extension of the spring, in such a manner that a series ofspeeds can be obtained intermediate to the normal and maximum speeds.

The numeral 4 designates stop indexes which have connection withdiaphragms or plates, not shown, disposed between the main plate and theleaf or shutter a. These parts 4 also serve as operating means for saiddiaphragms. Notched plates 5 connected with the partsv 4 coperate with-the shutters.

spring detents 6 attached to the main plate or frame to hold the parts 4and diaphragms in the desired adjusted position.

The time mechanism embodies a lever 7 which coperates with stops, notshown, on A latch 8 holds the time mechanism out of action wheninstantaneous exposure is desired.

The cylinder of the dash-pot has an opening 9 which is controlled by acap 10 or like part to regulate the flow of the air, whereby the speedof the piston 0 is regulated.'

The parts iust referred to are disclosed in detail in English Patent No.15,804, granted to me in 1907, and form no part of the presentinvention.

This invention is applicable to all shutters provided with a brake ordamping device.

Claims:

1. In a shutter mechanism, a tensioned shutter member, means for holdingthe same in retracted position, releasing means for said holding means,retarding mechanism for said releasing means, means for holding theretarding mechanism out of action, and a spring connection between saidretarding mechanism and said releasing mechanism.

2. In a shutter mechanism, a tensioned shutter member, means for holdingthe same in retracted position, releasing means for said holding means,a dash-pot, means for holding the movable member of the dash-pot infixed position, and a spring connection between the movable member ofsaid dashpot and said releasing means.

3. In a shutter mechanism, a tensioned shutter member, means for holdingthe same in retracted position, releasing means for said holding means,retarding mechanism for said releasing means, means for holding theretarding mechanism out of action, a spring connection between saidretarding mechanism and said releasing mechanism, and means forrendering said releasing mechanism inoperative.

4. In a shutter mechanism, a tensioned shutter member, means for holdingthe same in retracted position, releasing means for said holding means,a dash-pot, means for holding the movable member of the dash-pot infixed position, a spring connection between the movable member ofY saiddash-not and said releasing means, and means for locking the movablemember of said dash-pot.

5. A'shutter mechanism comprising apair of tensioned shutter members,separate means for holding said shutter members in retracted positionvunder tension, releasing mechanism for each of said holding means, meanscarried by one of said shutter mem bers for rendering` the releasingmechanism of other shutter member inoperative, Aprovements inphotographic shutters signed retardmg means, means for holding the rebyme this 17th lday of January, 1914.

tarding mechanism out of action, and a. JULES RICHARD. spring connectingsaid retarding means and Witnessesz 5 said last-mentioned releasing'mechanism. HANsoN C. COXE,

The 'foregoing specification of my 1m- REN THmIm.

